Information transmission system, transmitter, and transmission method as well as information reception system, receiver and reception method

• US 7,099,479 B1
• Filed: 08/25/2000
• Issued: 08/29/2006
• Est. Priority Date: 08/27/1999
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Asano, Tomoyuki, Oishi, Tateo, Ishibashi, Yoshihito, Matsuyama, Shinako, Muto, Akihiro, Kitahara, Jun
• Primary Examiner(s): Song, Hosuk
• Assistant Examiner(s): Dada, Beemnet W
• Application Number:
  US09/830,392
• Time in Patent Office: 2,195 Days
• Field of Search: 380/277, 380/278, 380/228, 380/239, 380/238, 380/203, 380/210, 380/281, 713/31, 713/189, 705/50, 705/51
• US Class Current: 380/281
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 2221/2107 File encryption
• CPC Class Codes: G06Q 30/06 Buying, selling or leasing transactions
• CPC Class Codes: G10K 15/02 Synthesis of acoustic waves synthesis of speech G10L13/00
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 63/045 wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption cryptographic mechanisms or cryptographic arrangements using a plurality of keys or algorithms H04L9/14
• CPC Class Codes: H04L 63/102 Entity profiles
• CPC Class Codes: H04L 63/12 Applying verification of the received information cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04L 9/0894 Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823

Abstract

Content data encrypted with a content key, the content key encrypted with an individual key specific to an information sending device, and the individual key encrypted with a distribution key that is updated in a predetermined cycle, and supplied are sent to an information receiving device, and the information receiving device decrypts the individual key with the distribution key, decrypts the content key with the individual key, and decrypts the content data with the content key. Thus, the information sending device does not have the distribution key, and accordingly piracy of content data can be prevented with a simple configuration. Also, the information receiving device sends the content key and a playback command to other apparatuses. Thus, other apparatuses can play back contents using the playback command and the content key. Furthermore, the information sending device decrypts the content key with the distribution key before being updated, and stores the same. Thus, contents purchased by an advance order can be actually purchased regardless of expiration dates of the distribution key. Furthermore, usage right is passed from a first information receiving device to a second information receiving device different in registration information at the tome of using contents. Thus, contents can be used among information receiving devices different from each other in registration information.

Claims

1. An information distribution system for distributing predetermined content data from an information sending device to an information receiving device,

said information sending device comprises:

first storing means for storing content data that is prohibited from being played by an information receiving device that does not include a content key;

second storing means for storing content data that is permitted to be played by an information receiving device that does not include the content key;

sending end controlling means for encrypting said content data with a content key, and encrypting the content key with an individual key specific to said information sending device; and

sending means for sending an encrypted individual key by encrypting said individual key with one of a plurality of distribution keys, each distribution key corresponding to a predetermined time period, to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key, and

said information receiving device comprises;

receiving means for receiving said content data encrypted with said content key and said content key encrypted with said individual key together with said encrypted individual key; and

receiving end controlling means for decrypting said individual key with one of said plurality of distribution keys, decrypting said content key with the decrypted individual key, and decrypting said content data with the decrypted content key; and

allowing decryption of said individual key within the predetermined time period associated with said distribution key, independent of a connection during said predetermined time period associated with said distribution key.

2. An information distribution method for distributing predetermined content data from an information sending device to an information receiving device, wherein said method comprises:

a first storing step for storing content data that is prohibited from being played by an information receiving device that does not include a content key;

a second storing step for storing content data that is permitted to be played by an information receiving device that does not include the content key;

a sending step of encrypting said content data with a content key, encrypting the content key with an individual key specific to said information sending device, and sending an encrypted individual key made by encrypting said individual key with one of a plurality of distribution keys, each distribution key corresponding to a predetermined time period, to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key, by said information sending device;

a decrypting step of receiving said content data encrypted with said content key and said content key encrypted with said individual key together with said encrypted individual key, decrypting said individual key with one of said plurality of distribution keys, decrypting said content key with the decrypted individual key, and decrypting said content data with the decrypted content key, by said information receiving device; and

allowing decryption of said individual key within the predetermined time period associated with said distribution key, independent of a connection during said predetermined time period associated with said distribution key.

3. An information sending device for sending predetermined content data to an information receiving device, said device comprising:

first storing means for storing content data that is prohibited from being played by an information receiving device that does not include a content key;

second storing means for storing content data that is permitted to be played by an information receiving device that does not include the content key;

sending end controlling means for encrypting said content data with a content key, and encrypting the content key with an individual key specific to said information sending device;

sending means for sending an encrypted individual key made by encrypting said individual key with one of a plurality of distribution keys, each distribution key corresponding to a predetermined time period, to said information receiving means together with said content data encrypted with said content key and said content key encrypted with said individual key; and

allowing decryption of said individual key within the predetermined time period associated with said distribution key, independent of a connection during said predetermined time period associated with said distribution key.

4. The information sending device according to claim 3, characterized in that said sending end controlling means encrypts said content key with said individual key supplied from the outside together with said encrypted individual key.

5. The information sending device according to claim 4, characterized in that said sending means sends said encrypted individual key made by encrypting said individual key with said distribution key that is updated periodically, which is supplied from the outside, to said information receiving device together with said content data encrypted with said content key and said content key encrypted with said individual key.

6. The information sending device according to claim 5, characterized in that said sending means sends said encrypted individual key appropriate to an update period, in said encrypted individual key for a plurality of periods given together in advance to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key.

7. An information sending method for sending predetermined content data to an information receiving device, wherein said method comprises:

a first storing step for storing content data that is prohibited from being played by an information receiving device that does not include a content key;

a second storing step for storing content data that is permitted to be played by an information receiving device that does not include the content key;

a encrypting step of encrypting said content data with a content key, and encrypting the content key with an individual key specific to said information sending device;

a sending step of sending an encrypted individual key made by encrypting said individual key with one of a plurality of distribution keys, each distribution key corresponding to a predetermined time period, to said information receiving device together with said content data encrypted with said content key and said content key encrypted with said individual key; and

allowing decryption of said individual key within the predetermined time period associated with said distribution key, independent of a connection during said predetermined time period associated with said distribution key.

8. The information sending method according to claim 7, characterized in that in said encrypting step, said content key is encrypted with said individual key supplied from the outside together with said encrypted individual key.

9. The information sending method according to claim 8, characterized in that in said sending step, said encrypted individual key made by encrypting said individual key with said distribution key that is updated periodically, which is supplied from the outside, is sent to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key.

10. The information sending method according to claim 9, characterized in that in said sending step, said encrypted individual key appropriate to an update period, in said encrypted individual key for a plurality of update periods given together in advance, is sent to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key.

11. A computer readable storage medium having a program stored therein for storing an information sending method, said method comprising:

a first storing step for storing content data that is prohibited from being played by an information receiving device that does not include a content key;

a second storing step for storing content data that is permitted to be played by an information receiving device that does not include the content key;

an encrypting step of encrypting predetermined content data with a content key, and encrypting the content key with an individual key specific to an information sending device;

a sending step of sending an encrypted individual key made by encrypting said individual key with one of a plurality of distribution keys;

each distribution key corresponding to a predetermined time period, to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key; and

allowing decryption of said individual key within the predetermined time period associated with said distribution key, independent of a connection during said predetermined time period associated with said distribution key.

12. The storing medium according to claim 11, characterized in that in said encrypting step, said content key is encrypted with said individual key supplied from the outside together with said encrypted individual key.

13. The storing medium according to claim 12, characterized in that in said sending step, said encrypted individual key made by encrypting said individual key with said distribution key that is updated periodically, which is supplied from the outside, is sent to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key.

14. The storing medium according to claim 13, characterized in that in said sending step, said encrypted individual key appropriate to an update period, in said encrypted individual key for a plurality of update periods given together in advance, is sent to said information receiving device together with said content data encrypted with said content key and a content key encrypted with said individual key.

15. An information distribution system for sending content data encrypted with a predetermined content key from an information sending device to an information receiving device,

said information sending device comprises:

first storing means for storing content data that is prohibited from being played by an information receiving device that does not include a content key;

second storing means for storing content data that is permitted to be played by an information receiving device that does not include the content key;

sending end controlling means for encrypting said content key with an individual key specific to said information sending device; and

sending means for sending at least said content key encrypted with said individual key, and an encrypted individual key made by encrypting said individual key with one of a plurality of distribution keys, each distribution key corresponding to a predetermined time period, to said information receiving device, and

said information receiving device comprises;

receiving means for receiving at least said content key encrypted with said individual key and said encrypted individual key; and

receiving end controlling means for decrypting said individual key with one of said plurality of distribution keys, decrypting said content key with the decrypted individual key, and storing the decrypted content key, before said distribution key is updated, thereby making it possible to decrypt said content after said distribution key is updated.

16. An information distribution method for sending content data encrypted with a predetermined content key from an information sending device to an information receiving device,

wherein said method comprises:

a first storing step for storing content data that is prohibited from being played by an information receiving device that does not include a content key;

a second storing step for storing content data that is permitted to be played by an information receiving device that does not include the content key;

a sending step of encrypting said content key with an individual key specific to the information sending device, and sending at least said content key encrypted with said individual key, and an encrypted individual key made by encrypting said individual key with one of a plurality of distribution keys, each distribution key corresponding to a predetermined time period, to said information receiving device, by said information sending device; and

a storing step of receiving at least said content key encrypted with said individual key, and said encrypted individual key, and decrypting said individual key with one of said plurality of distribution keys, decrypting said content key with the decrypted individuals key, and storing the decrypted content key before said distribution key is updated, thereby making it possible to decrypt said content after said distribution key is updated, by said information receiving device.